U.S. Pat. Nos. 3,183,991 to Gamaunt; 3,426,720 to Enos; and 4,079,995 to Thorpe illustrate articulated vehicles wherein the trailer is capable of motion about the vehicle roll plane to adapt the vehicle for movement over rough terrain, for example along the sides of hills, over rocky areas in which the left wheels are momentarily higher or lower than the right wheels, etc. When the vehicle is traveling over paved roads or smooth terrain, the roll motion may be a deterrent to high speed travel in that the trailer is apt to tip over or sway from side to side, thus making the steering and control of the vehicle difficult or tiring on the driver.
U.S. Pat. No. 4,079,955 illustrates a latch mechanism for locking the trailer out of its roll mode capability when it is intended to operate the vehicle on smooth terrain. The present invention is directed to hydraulic cylinder mechanisms for locking out the roll mode capability. The use of hydraulic cylinders is advantageous in that control valves for the cylinders can be remotely operated, as for example at the vehicle dash board. Also, there is no necessity to align a latch with a keeper as in the arrangement shown in U.S. Pat. No. 4,079,955. The hydraulic cylinders can, with suitable design, be controlled to provide different degrees of resistance to roll motion, from zero resistance to total resistance, i.e. complete lock out.
The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without payment to me of any royalty thereon.